Composite grinding-rolls.



Patented Aug. 6, !901.

w. E. ARNOLD COMPOSITE GBINDING BOLLS.

(No Model.)

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UNITED STATES PATENT OFFICE.

WILBER E. ARNOLD, OF MADIsoNvILLn-oHIo.

MCOIVVIPOSITE GRINDING-ROLLS.

SPECIFICATION forming' part of Letters Patent No. 679,821, dated August 6, 1901.

Application filed August 18. 1899. Seria-1 No. ?27,623. (No model.)

.Ta all whom it may cancer-n:

Be it known that I, WILBER ARNOLD,`a citizen of the United States, residing at Madisonville, in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in Composite Grinding- Rolls; and I do hereby declare the following to be a full, clear, and exact description of the inventon, reference being had to the acconpanying drawings, which form a part of this specification.

This invention relates to netallic grindin grolls of the kind which are built up in sections and of which rolls usually two operate in conjunction with each other, they being mounted for such purpose with their grinding-surfaces opposite each other, the operation being by rotation in opposite directions.

It relates more particularly to rolls used for reducing grain to flour, and the object of so building them up in sections of metal of alternate hardness is for the purpose of ren dering them self-sharpening.

My invention consists of the Construction as hereinafter described and claimed and as illustrated in the'accompanying drawings, in which- Figure l shows two grinding-rolls Operating in conjunction with each other in the usual manner and arranged as contenplated by my invention. Fig. 2 is an enlarged vertical section of a number of the end disks of one of said rolls. Fig. 3 is anend View, and Fig. 4 in an edge view shows a modified form of my invention. Fig. 5 in a similar view shows another modification.

Referring to Figs. 1 and 2, letters A and B indicate the disks referred to before, and of which those represented by A'are of a harder metal than those designated by B. As to one particular roll, they are all of equal diameter and have central openings or bores a and b, which are fitted to a shaft C, which may be round or polygonal, as shown in Fig. 2. The disks are mounted edgewise on their shaft in a manner that one of the harder metal alternates 'with one of softer metal, and they are endwise confined on such shaft by nuts c c'. In addition to having the disks thus alternating in one roll as to the degree of hardness of material they further alternate in position in a manner that the edge of a soft disk in one roll operates opposite of the softer disks, whereby continually close and contacting grinding-surfaces are maintained between the two rolls. The larger part of the wear is thus alternately transferred from the grinding edge of the soft disks to those of the hardermaterial, which alternate wear down keeps the grinding-surfaces in operative condition and obviates redressing by hand.

As shown in Figs. 3 and 4, the hard-metal disk A' is provided with angular crimps a' and the soft-metal disk B' has similar crimps b' in order that said disks may nest the one within the other when mounted upon a shaft, so as to form a truly cylindrical roll. By thus corrugating or bending the disks from their centers out to their circunferences the grinding-surfaee of the roll instead of exposing the edges of the disks in parallel zones or stripes, as in Fig. 1, will show zigzag or chevron-shaped edges, as shown in Fig. 4:. Therefore a vertical plane passing directly across such a roll would cut alternately through a portion of the hard and soft disk, and assuming this plane to be one of an indefinite number of grinding-surfaces of said roll it :is evident the wear of such alternate surface would be reduced to a minimum.

In Fig. 5 the angular crinps are omitted and their work is accomplished by providing the disks with wave-shaped bends or rounded corrugations a," b". In each of these cases these crinps or corrugations are arranged radially.

Having described my invention, I claim as newl. A pair of grinding-rolls each comprising two sets of grinding-disks of which one set is of softer metal than the other, all of equal diameter and each provided with a central IOO 2 V i v i r 679,821

and upon which the two sets of disks are mounted side by side toform grinding-roils and in a nannethat one'disk of softer metl `bore, a. shft to which these bores arefitted i 2. A composite -grinding-roll consistihg of alti'ntehardand soft metaHic-disks, having -adially-arranged corrugations or crim ps In testimouy whereof I affix my signature in presence of two witnesses. r

W'ILBER E. ARNOLD. i

` V Witnessesz J AMES H. LAYMAN, EARLE R. PASSEL. 

